Sand-blast device



May 14, 1929. wYTcHERLEY 1,712,804

SAND BLAST DEVICE Filed July 26, 1926 I MEBBMEEUII Paten'tecl May 14,1929.

UNITED STATES EDWARD WY'ICHERLEY, OF PEORIA, ILLINOIS.

BAND-BLAST DEVICE.

Application filed July 26, 1926. Serial No. 124,947.

This invention relates to a sand blast device for use in inscribing onstones, renovating stone of all'descriptions, and for other uses whereina combined blast of air and sand, or air and other material, is adaptedto be mixed and projected under high pressure.

One of the objects of the invention 18 in the provision of a sand blastdevice of simple construction, the same being adapted to be used eitheras a portable or as a unitary structure.

Another object is in the provlslon of a sand blast device fashioned in amanner to insure, at all times, an even feed of sand.

Still another object is in the provision of a sand blast devicecomprising a reservoir, wherein there is such an arrangement of air andfeed pipes as to insure the proper discharge of sand and air.

Other objects will appear in the following specification taken inconnection with the annexed drawings, in which the single figure showsin side elevation, partially in section, my sand blast device which maybe utilized either as a unitary or as a .portable structure. I

Referring to the drawings, I have shown the main reservoir 10, which maybe of various ca acities, as desired, the same having a suitable closureportion 11. A main air 1nlet pipe 12 is shown, air pressure beingadapted to be applied to such air pipe by any neumatio means desired.The air nlet plpe 12 enters the reservoir at the omt 13, assuming asmaller diameter, as s own at 14, and is then angled in such manner thatthe discharge end 15 opens into the lower end 16, of a sand blast pipe17, the latter being of considerably larger diameter than the air pipe.

The sand blast pipe 17 has an aperture 18 disposed adjacent the upperend thereof, said aperture opening into the upper portion of thereservoir at a point above the sand level in the present instance shownat 19. T1113 sandblast pipe is connected to a pipe 20, which carries thesand andair mixture through a flexible coupling 21 to a nozzle 22. Anair by-pass is shown at 23, the same having a valve member 24 thereincontrolling the amount of air to be by passed and therefore acting as ameans for adjusting the blast. A second valve member 25 similarly actsas a means for adjusting the blast, as desired.

Referring to the operation of the present device, air under highpressure passes through the tube 12, and into the reservoir 10, throu hthe tube 14. Means for controlling t is air pressure is provided notonly in the valve 24, but also in valve 25. The blast of air that isprojected from the opening 15 picks up the sand around the lower end .16of the pipe 17 and carries it upwardly through the said pipe, thencethrough the pipe 20, flexible coupling 21, and finally out the nozzle22, said nozzle being restricted, as shown, in a manner to increase thespeed of the projected sand and air particles propelled by the highpressure air.

In'order to insure the forcing of the sand to the lower part of thereservoir 10, the aperture 18 is provided in the sand blast pipe,whereby a portion of the air blast I passes through said aperture andexerts a downward pressure upon the sand, which is maintained at a levellower than this aperture. This pressure upon the upper side of thereservoir insures the collection of sand about the air blast nozzle 15.This aperture 18, as above described, not only provides for pressureupon the abrasive content in the reservoir, but also operates in a moreimportant capacity to automatically compensate for the excessive amountof sand contained in the mixture that is being projected through thetube 17 and finally to the nozzle 22. In other words, there is a tend--ency for the sand which is picked up by the air pipe 15 and projectedthrough the outlet pipe 17 to contain an excessive amount of sand andunless there were some means permitting escape of said sand, same wouldobviously finally accumulate at the small orifice in nozzle 22 andtherefore prevent satisfactory operation of the device in that merely asmall trickle of sand would be projectedtherefrom.

It may be stated at this time that unless some means is provided in anapparatus of the character described herein for automaticallycompensating for the excess amount of abrasive that is being rapidlyprojected through the pipe 17 that said device obviously would notoperate efficiently. As a matter of fact, the feature of compensatingfor this excessive amount of abrasive is of paramount importance and thefeature of exerting an air pressure upon the upper. layer of-theabrasive is of lesser importance in view oi the fact that the reservoiritseH is, .underordinary conditions, adapted to contain approximatelyone thousand pounds of abrasive, which weight would force said abrasiveabout the ejector end of the outlet pipe 17 and iirsuch manner that itwould readily picked up by the air inlet 15. Sim larly, the fashioningof the sand blast pipe 17 of larger diameter than the air pipe, insuresthe desired sand feed into the air blast, with a consequent evening ofthe blast at the nozzle. a

The various classes of work to which this device is adapted, makesnecessar' means' for adjusting the amount of air elivered to the sandand hence valve members 24 and 25 have been provided to control theamount of air to be used. Adjustment of these valve members obviouslyresults in the desired mixture of sand and air.

What I claim is:

1. In a sand blast device, in combination a reservoir adapted to receivea supply 0 abrasive fora portion of its depth, a top on the reservoir,an air inlet projecting into said reservoir to a point below the levelof the abrasive, and an outlet pipe disposed within the reservoir, theejector, end of the pi e lying adjacent the open end of the air mfetpipe, said outlet pipe pro'ecting from the reservoir and being provldewith means for removing an excess supply of abrasive from said pipe.

2. In a sand blast device, in combination a reservoir adapted to receivea supply of abrasive for a portion of its depth, a top on the reservoir,an air inlet projecting into said reservoir to a'point below the levelof the abrasive, and an outlet pi e of larger diameter than the inletpipe disposed within the reservoir, the ejector end of said ipe 1yingadjacent the open end of the air inlet pipe, said outlet p1pe projectingfrom the reservoir and terminating in a nozzle means being provided insaid outlet pipe for discharging abrasive therefrom in excessof thenormal capacity of the nozzle 3; In a sand blast device, in combinationa reservoiradapted to receive a supply of abrasive for a portion of itsdepth, a top on the reservoir, an air inlet projecting into saidreservoir to a point below the level of the abrasive, and an outlet ipeof'lar r diameter'than the inlet pipe isposed within the reservoir theejector end 0 said outlet pi e lying adjacent the open end of the air inet i e, said outlet i e assin throu h the sga e above the su f ce of thabrasi ve and projecting from the reservoir, means being provided in theoutlet pipe at a point above the surface of the abrasive for providingair pressure in the space above the abrasive and for dischargingabrasivematerial in excess of the normal capacity of the nozzle when thecapacity of the nozzle has been reached.

7 4. In a'sand blast device, in combination, a pressure tank adapted toreceive a supply of abrasive for a portion of its depth, an air inletprojecting into said tank to a point below thelevel of the abrasive, andan outlet pi e of larger'diameter than the inlet pipe isposed within thetank, the ejector end of said outlet pipe lying adjacent the i Intestimony whereof I have hereunto affixed my signature.

EDWARD WYTCHEBLEY.

